Anthony Wing Kosner
, ContributorQuantum of Content and innovations in user experienceOpinions expressed by Forbes Contributors are their own.

"I like you Siri, you're going places." So ends Martin Scorcese's paid homage to the iPhone's virtual assistant. But with the introduction of Google's Voice Search for iOS, Siri's shortcomings are becoming more apparent. The problem is contextual data. Google has (lots of) it and Apple has to buy it piecemeal from Yelp, WolframAlpha, Yahoo and, yes, Google.

In a test done by Piper Jaffray analyst Gene Munster in June (and reported by MacRumors), Google accounted for 60% of Siri's data diet:

And Apple, in its Android Rage, seems to be looking to sever ties with Google as much as possible. Kind of looks like Siri is going nowhere, Martin.

The Google Search app for iOS now has a voice icon just like its Android built-in equivalent, and it works remarkably well. This is not (yet) a personal assistant. Voice Search only searches the web at present, but with the strong likelihood that a user's Gmail and Apps data will become searchable (by the user) as well, Google is within striking distance of Siri's functionality.

Plus, Google has improved its user interface for certain kinds of informational results, like flight tracking and currency conversions, on mobile devices, and now displays them in a nice, big, display box at the top of the screen. These are borrowed from the "cards" in the Google Now built-in app available on the Nexus 7 tablet. And soon, if you search for a popular topic ("famous jazz composers," for instance) the search results will be broken out in a visual carousel at the top of the page. All of this is supported by Google's Knowledge Graph (move over Facebook), that "currently contains more than 500 million objects, as well as more than 3.5 billion facts about and relationships between these different objects." And this is not a static resource, but one that is "tuned based on what people search for, and what we find out on the web."

When all of this contextual information includes a user's own data it approaches personal assistant status. Google Now doesn't reschedule your appointments for you like Siri, but it does show you relevant information when you need it, based on your mail, calendars and other Google apps you are using. This is a great example of Google doing what only it can do, and what the video below shows for the Nexus 7, will soon be available for mobile devices and the desktop.

It is notable that Google has not adopted any Siri-like personas for either its Voice Search or its new Google Now services. Considering the troubles Google has with Apple over Android, it is not surprising that they are taking a different tack. Google being Google, though, they have a sure-fire Siri-killer at their disposal. If it opens the API's for all of this to developers so that they can create custom personas on top of Voice Search, Google Now and Knowledge Graph, Siri will certainly be crowded out by a cacophony of more well-informed voices tuned to specific personality types.

But Apple is not sitting on its hands for all of this. As Daniel Eran Dilger writes on the Apple Insider blog, Google faces some roadblocks and Apple can add to them. First off, Google Now requires the latest version of Android (Jellybean 4.1) and at the moment, less than 1% of Android users have upgraded. "A full 80 percent of the active user base are suck with a version of Android 2.x, which came out 2010," notes Dilger. "In contrast, Apple just noted that 80 percent of iOS users are running the latest iOS 5. Apple has also sold more Siri-capable iPhone 4S units than all of its previous generation of iPhone combined."

Voice Search and the card elements from "Now" are Google's attempts to get around that fragmentation and get the functionality in users' hands immediately. But any apps that Google submits to the App Store for approval can be held up by Apple if it deems them too similar in functionality or design to Siri. Dilger reminds us that, "Apple previously held up approval of Google Voice for over a year, and kept Google's Latitude friend finder app in limbo for two years as it considered the features. This left Google to rely upon web app alternatives to native titles in the App Store."

While it is not certain that Siri will lose the race with Google, she is certainly engaged in a high-speed car chase through increasingly narrow streets.